Laundry apparatus



Feb. 28, 1961 Filed Nov. 19. 1956 T. E. DAVIDSON 2,972,817

LAUNDRY APPARATUS 6 Sheets-Sheet 1 INVENTOR. THOMAS E. DAVIDSON T. E.DAVIDSON LAUNDRY APPARATUS Feb; 28, 1961 Filed Nov. 19. 1956 sSheets-Sheet 2 IN VEN TOR.

HIS A TTOR/Vf Feb. 28, 1961 T. E. DAVIIVDSON 2,972,817

LAUNDRY APPARATUS Filed Nov. 19. 1956 6 Shets-Sheet' a fi ,1 l

43/ if If 6f fi IN VENTOR.

THOMAS E. DAVIDSON v (QM/J H15 )4 T TORN T. E. DAVIDSON LAUNDRYAPPARATUS Feb. 28, 1961 6 Sheets-Sheet 4 Filed Nov. 19. 1956 INVENTOR.THOMAS E. DAVIDSON HIS A TTORNE) Feb. 28, 1961 T. E. DAVIDSON 2,972,817

LAUNDRY APPARATUS Filed Nov. 19. 1956 6 Sheets-Sheet 5 INVENTOR. THOMASE. DAVIDSON ms ATTORNY Feb. 28, 1961 1501111155011 2,972,817

LAUNDRY APPARATUS Filed Nov. 19. 1956 6 Sheets-Sheet 6 HEATING INVENTORTHOMAS E.0AVID$0N BY z orney LAUNDRY APPARATUS Thomas E. Davidson,Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich., acorporation of Delaware Filed Nov. 19, 1956, Ser. No. 623,051

3 Claims. (CI. 34-45) This invention relates to a domestic appliance andmore particularly to laundry apparatus such as washers, dryers, andcombined washers and dryers.

In laundry apparatuses provided with heaters it is important to providea reliable thermostatic control for controlling the heaters thereof tomaintain proper temperature and to prevent over heating. Especially inhorizontal rotatable drum type of dryers is it important to locate thethermosensitive element of the thermostat controls at a location orlocations most responsive to the dryness of the laundry.

It is an object of this invention to provide laundry apparatus with amore sensitive temperature control of the heaters thereof which is solocated that it more readily will prevent damage to the laundry and alsoto the apparatus.

It is another object of this invention to provide a laundry dryer with areliable sensitive temperature control so located that it moreaccurately will, terminate or reduce the heating just before the laundrybecomes completely dry.

It is still another object of this invention to provide a laundry dryerwith a reliable temperature control having its thermosensitive elementlocated in a relatively cool place where the temperature change isrelatively large as the laundry approaches a state of dryness.

These and other objects are obtained in the form shown in the drawingsin which a horizontal rotatable drum rotates within a cylindrical drumcasing. The drum casing is provided with a water film condenser in thelower quarter on the ascending side of the drum as it rotates clockwise.Drying heaters are .also provided in the top of the drum casing. Whenthe apparatus is used for washing, a water heater may be provided at thebottom of the front of the drum casing. The bottom of the front of thedrum casing is provided with a thermostat for terminating the waterheating and a second safety thermostat for preventing over heating.

To terminate the operation of the heaters for drying when the laundrywithin the drum approaches a state of complete dryness there is providedin the periphery of the drum between the drying heaters and the bottomof the water film condenser a low temperature thermostat and a hightemperature thermostat which are set to stop the heating when thelaundry reaches astat e of dryness consistent with the fabric and themaximum temperatures which the fabric can withstand. In addition twodryer safety thermostats are provided. One of these may be positionedbetween the top of the water film condenser and the adjacent dryerheater while a second may be placed adjacent the high and lowtemperature thermostats near the bottom of the water film condenser.These safety thermostats may be connected in series with each other andin series with all of the dryer heaters.

'Further objects and. advantagesv of the present invention-will beapparent from'the following. description,

reference being had to the accompanying drawings,

2,972,817 Patented Feb. 28, 1961 wherein a preferred form of the presentinvention is clearly shown. I

In the drawings:

Figure 1 is a front view of a combined washer-dryer embodying one formof my invention with the front wall of the cabinet removed showing thefront of the casing and its suspension;

Figure 2 is a rear view of the casing and its suspension with theremainder of the cabinet removed;

Figure 3 is a vertical sectional view taken along the axis of the drumand casing;

Figure 4 is a front view of the combined washer-dryer with one halfthereof shown in a vertical section transverse to the axis of the drum;

Figure 5 is a fragmentary view of the lower portion. of the casing insection showing the water heater and its controls taken along the line55 of Figure 6;

Figure 6 is a fragmentary bottom view of the portion of the casing shownin Figure 5;

Figure 7 is a fragmentary view of the lower portion of the drum casingpartly in section showing the location of the water heater and the threedryer thermostats; and

Figure 8 is a control and wiring diagram for the washer and dryer shownin previous figures.

Referring now to the drawings and more particularly Figures 1 to 3 thereis shown a combined washer-dryer including a box-shape cabinet 20 formedof a base 19,. side walls 22 and 18, a rear wall 17, a top wall 2 6, anda front wall in two sections 16 and 15. The section 16 is provided witha rectangular door 56 providing access to the interior of the drumcasing 30 and the drum 40. The drum 4% is removably mounted upon thetapered bearing shaft 58 rotatably mounted in the ball bearings. 59which are supported by the rear wall of the drum casing 30. The rear endof the shaft 58 is provided with a large pulley 66} connected by a belt61 to the transmission 62 and the electric drive motor 63. The drumcasing 30 is provided with a lower bracket 64 pivotally connected at itsends to the lever arms 65 and 66 fixed. to the ends of the horizontalbar 67 which is pivotally mounted in the bearings 68 fixed to the base19. This lever arrangement guides the casing substantially in a verticaldirection while its vibrations are controlled by the hydraulic shockabsorbers 69 pivotally connecting the two sides of the casing 30 withthe base 19. Coil springs 79 surround the hydraulic shock absorbers forsupporting the drum casing 30.

For washing, water is introduced into the drum casing from a feed pipe71 having a goose neck discharge 72 into the funnel 73 from which thewater flows by gravity through the pipe 74 into the horizontal trough150. The Water overflows from this trough 150 over the lips 75 down theinner surface of the left quarter segment of the periphery casing 30 toits bottom portion. The feed pipe 71 receives water from a valve body 77which includes a hot water solenoid 121 and a cold water moisture fromthe laundry. At the end of the washing and rinsing periods and duringthe drying period, water is pumped out of the bottom of the casing 30through the hose 81 by the pump 82 which discharges through.

the hose 83 to a suitable drain. The pump is driven by.

the 'motor 63.

For the purpose of heating the water in the event that the supply of hotwater is inadequate, there is provided the sheathed tubular heater 431directly adjacent the front of the drum casing 3 and having downwardlyextending terminals extending through the bottom wall as shown best inFigures 5 to .7 and fastened in place by the nuts 85. To control thisheater v431 there is provided a water heater thermostat 418 fastenedinto an opening in the lower front of the drum casing 30 as is shown inFigures 1 to 7 so that its thermosensitive element is in'heat transferwith the water in the bottom of the drum casing for terminating theheating of the water when the water reaches the desired temperature. Thethermostat 41%; may be set to close at 150 F. and to reopen at 120 F. Inaddition, directly at one side there is provided the water temperaturesafety thermostat 419 set to open at a higher temperature such as 170 F.and to reclose at 120 P. which is contacted by an intermediate part ofthe heater 431 to respond quickly to high heater temperatures to protectand deenergize the water heater in the event that the heater 431 becomesenergized when there is no water in the casing. It also prevents veryhigh water temperatures in case of failure of the thermostat 413.

' After the washing and rinsing periods, the drum at) is rotated atcentrifuging speeds by the motor 63 and the transmission altocentrifugally dry the laundry therein. Thereafter there are energizedthe heaters 456 and 451 located in the two bumps 91 in the oppositeupper quarters of the eriphery of the drum casing 3%. These heaters heatthe laundry within the drum as it rotates at a slow speed flailing anddriving the moisture out of the laundry. This moisture vapor migrates tothe water film flowing from the trough 159 down the inside of thecasing. The drum 4t) rotatesin a clockwise position as viewed from thefront as shown by the arrow in Figure 4. The heaters 45% and 451 operateuntil the laundry reaches a state of nearly complete dryness. However,since certain fabrics can withstand fairly high temperatures and manyother fabrics cannot, there are provided a high temperature thermostat4% and a low temperature thermostat 424 in the lower por tion of theperiphery of the drum casing directly opposite the water film condenserbut somewhat nearer the bottom of the drum. The thermostatsdlii and 424respectively control high and low energy arrangements of the dryerheaters 45% and 451. These thermostats may for example, be set to closeat 210 F. and 177 F. respectively. The closing of these thermostats actsto operate the timer to terminate the heating of the heaters 451? and451 but to continue the how of water under the control of the solenoidvalve 475 and the rotation of the drum under the control of the switch51. These thermostats 426 and 424 are set to reopen at 170 F. and 147 F.respectively.

I have found that at these locations as the laundry approaches a stateof dryness in the drum the temperature rises rapidly so that thetermination of the heating by the eaters 45% and 451 can be terminatedwith considerable accuracy. in this position between the thermostats 420and 42 4 and the bottom of the casing 3G I provide the safety thermostat1d) which is set to open to deenergize the heaters 45% and. 451 when thetemperature reaches 225 5. and to closeat 175 F. This will operate incase of failure of the heaters to. be deenergized through the timer bythe thermostats 42% or 424. In addition connected in series with thethermostat 16'9 is a second thermostat 174} located on the opposite sideof the periphery of the casing directly between the top of the waterfilm condenser and the trough 154i and the heater 4%. This location isespecially sensitive to the failure of water flow. as well as thefailure of the drum to rotate and the failure of cooling air flow overthis location. Therefore it provides important added safety inpreventing damage to the laundry and to the apparatus in the event offailure of the controls. This second thermostat 170 is preferably asingle pole double throw temperature responsive switch having a normallyclosed contact connected to the conductor 171 in Figure 8 and a normallyopen contact connected to the conductor 183 to energize the timer motor400 to bring the cycle to its conclusion.

The apparatus may be controlled by any suitable control arrangements.One example is shown in Figure 8 in which the timing motor 400 through ashaft 21 drives the cams 23, 27, 31, 35, 39, 41, 45 and 49 as well asthe combined knob and dial of 55. A water temperature selector 147 isprovided for controlling the water heater 431 and the hot and cold watersolenoids 121 and 123. A dryer heat selector 185 through the shaft 1&9and the cam 197 operates the double throw switches 187, 195 and 421 toselect either of the thermostats 420 or 424 and either a high or lowenergy circuit arrangement for the dryer heaters 450 and 451 forcontrolling the drying cycle. In addition there is also provided a waterlevel control 95. The thermostats 170, 418, 420 and 424 restart thetiming motor 400 to rotate the cams away from the heating position tothe next operation. The safety thermostat 170 also directly shuts offthe heaters. The water temperature safety thermostat 419 and the dryersafety thermostat 16? act only to deenergize their respective heaters431 and 456 and do not affect the operation of the timing motor 400.

Further disclosure of this control system is to be found in thecopending application of myself and Edward I. Frey, S.N. 548,644, filedNovember 23, 1955, which issued on March 15, 1960, as Patent 2,928,267.

With the above described arrangements of thermostats I have provided animproved control of water heating and drying.

While the form of embodiment of the invention as herein disclosedconstitutes a preferred form, it is to be understood that other formsmight be adopted, as may come within the scope of the claims whichfollow.

What is claimed is as follows:

1. A laundry apparatus including a drum casing, a rotatable drum withinthe casing, heating means within and extending over the greater part ofthe upper portion of said casing for heating laundry Within said drum,condensing means extending from the mid-point on one side of the drum tothe lower portion of the casing for condensing moisture vaporized fromthe laundry in said drum by the heating means, said heating means beinglocated in close spaced relation with the upper part of the condensingmeans, and thermostatic control means operably connected to said heatingmeans for controlling said heating means, said thermostatic controlmeans having a thermosensitive element exposed upon the inner peripheryof said casing between the adjacent portions of the heating means andthe condensing means.

2. A laundry apparatus including a drum casing, a rotatable drum withinthe casing, means for rotating the I drum in one direction of rotationwithin the casing, heating means within the upper portion of said casingfor heating laundry within said drum, condensing means in a lowersegment of the side of the casing on which the drum periphery ascends,and a higher and a lower temperature thermostatic switch means eachhaving a thermosensitive operating element located at the lower portionof the casing on the side opposite the condensing means, a timer havinga first time controlled switch for terminating the operation of theheating means and a second time controlled switch for terminating therotation of the drum subsequent to the termination of the operation ofthe heating means, said timer including a timer drive motor, electriccircuit means connecting said higher and lower temperature thermostaticswitch means in parallel circuit with each other and in series with saidtimer drive motor to operate said timer drive motor when the, selectedhigher or lower temperature is reached, electric circuit meansconnecting said first time controlled switch in series with said heatingmeans for deenergizing said heating means at the end of the heatingperiod, electric circuit means connecting said sec- 0nd time controlledswitch in series with said means for rotating the drum for stopping therotation of the drum subsequently to the end of the heating period, andselective switch means for selectively connecting said higher and lowertemperature switch means into energizing relation with said timer tostart said timer when the selected higher or lower temperature isreached.

3. A laundry apparatus including a drum casing, a rotatable drum withinthe casing, means for rotating the drum in one direction of rotationwithin the casing, heating means within the upper portion of said casingfor heating laundry within said drum, condensing means in a lowersegment of the side of the casing on which the drum periphery ascends,said heating means being located in close spaced relation with the upperpart of said condensing means, an electric circuit operably connected tosaid heating means, a thermostatic switch means connected in saidelectric circuit in series with said heating means, said thermostaticswitch means having a thermosensitive element located in said drumcasing between said heating means and said condensing means on the sideof the casing'on which the drum periphery ascends for controlling saidheating means.

References Cited in the file of this patent UNITED STATES PATENTS2,279,656 Chamberlin et a1. Apr. 14, 1942 2,644,245 Hammell et a1. July7, 1953 2,701,956 Duquenne Feb. 15, 1955 2,720,037 Erickson Oct. 11,1955 2,743,533 Smith May 1, 1956 2,797,497 Engel et al. July 2, 19572,807,890 Stone Oct. 1, 1957

